JPWO2015019402A1 - Permanent magnet embedded rotary electric machine - Google Patents

Abstract

The present invention provides a permanent magnet embedded type rotating electrical machine that can suppress a decrease in the amount of magnetic flux of a permanent magnet and can efficiently cool the permanent magnet. In this permanent magnet embedded type rotating electrical machine, the rotor 15 is formed by laminating and integrating electromagnetic steel plates, and the rotor core 17 fixed to the shaft and the outer peripheral side of the rotor core 17 are respectively penetrated in the axial direction. A plurality of magnet housing holes 20 formed in the circumferential direction and permanent magnets 21 housed in each of the magnet housing holes 20, and an adhesive 22 is provided on the inner wall surface of the magnet housing hole 20. The permanent magnet 21 is disposed only between the outer wall surface 20 a located radially outward and the outer surface 21 a located radially outward of the surface of the permanent magnet 21, so that the permanent magnet 21 is placed on the outer wall surface 20 a of the magnet housing hole 20. The cooling flow path 23 in which the refrigerant is flown and fixed in a single-sided manner is located on the inner surface 21b positioned radially inward of the surface of the permanent magnet 21 and the inner wall surface 20b positioned radially inward of the inner wall surface of the magnet housing hole 20. It consists of.

Description

  The present invention relates to a permanent magnet embedded rotary electric machine in which a permanent magnet is embedded on the outer peripheral side of a rotor core, and more particularly to a cooling structure for a permanent magnet embedded in a rotor core.

  In a conventional embedded permanent magnet rotating electric machine, a permanent magnet is disposed in a cavity formed in the rotor core so as to extend in the direction of the rotation axis, and an insulating member is formed so as to cover the entire inner wall surface of the cavity. The permanent magnet was cooled by flowing a coolant through a cooling flow path constituted by the surface of the insulating member and the inner surface of the insulating member (see, for example, Patent Document 1).

  In another conventional permanent magnet embedded rotary electric machine, an annular outer yoke portion in which a permanent magnet is embedded, an annular inner yoke portion disposed inside the outer yoke portion, and an outer yoke portion The rotor is configured by the ribs connecting the inner peripheral surface of the inner yoke portion and the outer peripheral surface of the inner yoke portion, and the groove portion is formed on the inner peripheral surface of the outer yoke portion so as to extend from one end portion in the axial direction to the other end portion. Was. Then, the cooling oil supplied to the through hole constituted by the inner peripheral surface of the outer yoke portion, the outer peripheral surface of the inner yoke portion and the ribs is guided into the groove portion by centrifugal force, and flows smoothly through the groove portion. The permanent magnet was cooled (for example, refer to Patent Document 2).

JP 2013-17297 A Japanese Patent No. 5097743

  However, in the conventional permanent magnet embedded rotary electric machine described in Patent Document 1, since the insulating member is formed so as to cover the entire inner wall surface of the cavity, the sectional shape of the cavity is larger by the space for forming the insulating member. Become. Thereby, the distance between a permanent magnet and the inner wall face of a cavity becomes long, the magnetic resistance between a permanent magnet and a rotor core increases, and there existed a subject that the amount of magnetic flux of a permanent magnet was brought about.

  Further, in the conventional permanent magnet embedded rotary electric machine described in Patent Document 2, since the cooling oil flow passage is formed between the outer yoke portion and the inner yoke portion, the heat of the permanent magnet is transferred to the outer yoke portion. The heat is dissipated to the cooling oil via the, and there is a problem that the permanent magnet cannot be cooled effectively.

  The present invention has been made to solve the above-described problems. The amount of the adhesive for fixing the permanent magnet to the inner wall surface of the magnet housing hole is reduced to reduce the cross-sectional area of the magnet housing hole. The distance between the magnet housing hole and the inner wall surface is shortened to suppress the decrease in the amount of magnetic flux of the permanent magnet, and the cooling flow path is configured so that the refrigerant directly cools the permanent magnet. It is an object of the present invention to obtain a permanent magnet embedded type rotating electrical machine that can be cooled rapidly.

  A permanent magnet embedded rotary electric machine according to the present invention is formed by stacking and integrating an annular stator core, a stator having a stator coil wound around the stator core, and an electromagnetic steel plate, and a shaft. A rotor core that is fixed to the stator core and rotatably disposed inside the stator core, and a plurality of magnets that are formed so as to penetrate the outer peripheral side of the rotor core in the axial direction and are arranged in the circumferential direction. And a rotor having a permanent magnet housed in each of the magnet housing holes. And the adhesive is disposed only between the outer wall surface located radially outward of the inner wall surface of the magnet housing hole and the outer surface located radially outward of the surface of the permanent magnet, A permanent magnet is offset to the outer wall surface of the magnet housing hole, and a cooling flow path through which the refrigerant flows is an inner surface located radially inward of the surface of the permanent magnet and a diameter of the inner wall surface of the magnet housing hole. It is comprised by the inner wall surface located in a direction inner side.

  According to this invention, the permanent magnet is fixed to the outer wall surface positioned radially outward of the inner wall surface of the magnet housing hole, and the cooling flow path through which the refrigerant flows is positioned radially inward of the surface of the permanent magnet. And an inner wall surface located radially inward of the inner wall surface of the magnet housing hole. Therefore, the refrigerant flowing through the cooling flow path is in direct contact with the inner surface of the permanent magnet, and the permanent magnet can be effectively cooled.

  In addition, since the adhesive is disposed only between the outer wall surface located radially outward of the inner wall surface of the magnet housing hole and the outer surface located radially outward of the surface of the permanent magnet, The amount of the agent is small, and the cross-sectional area of the magnet housing hole can be reduced. Therefore, the distance between the permanent magnet and the inner wall surface of the magnet housing hole is shortened, and an increase in magnetic resistance between the permanent magnet and the rotor core is suppressed. Thereby, the fall of the magnetic flux amount of the permanent magnet resulting from the increase in magnetic resistance can be suppressed.

It is sectional drawing which shows the permanent magnet embedded type rotary electric machine which concerns on Embodiment 1 of this invention. It is an end elevation which shows the rotor core in the permanent magnet embedded type rotary electric machine which concerns on Embodiment 1 of this invention. It is a perspective view explaining the state which incorporated the rotor core in the stator in the permanent magnet embedding type rotary electric machine which concerns on Embodiment 1 of this invention. It is a flow which shows the drive control method of the external oil feeding apparatus in the permanent magnet embedding type rotary electric machine which concerns on Embodiment 1 of this invention. It is sectional drawing which shows the permanent magnet embedded type rotary electric machine which concerns on Embodiment 2 of this invention. It is sectional drawing which shows the permanent magnet embedded type rotary electric machine which concerns on Embodiment 3 of this invention. It is an end elevation which shows the rotor core in the permanent magnet embedding type rotary electric machine which concerns on Embodiment 4 of this invention. It is an end elevation which shows the rotor core in the permanent magnet embedded type rotary electric machine which concerns on Embodiment 5 of this invention. It is an end elevation which shows the state at the time of the motor stop of the rotor core in the permanent magnet embedded type rotary electric machine which concerns on Embodiment 5 of this invention.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of a permanent magnet embedded type rotating electrical machine of the invention will be described with reference to the drawings.

Embodiment 1 FIG.
1 is a cross-sectional view showing a permanent magnet embedded type rotating electrical machine according to Embodiment 1 of the present invention, and FIG. 2 is an end face showing a rotor core in the permanent magnet embedded type rotating electrical machine according to Embodiment 1 of the present invention. 3 is a perspective view for explaining a state in which a rotor core is incorporated in a stator in a permanent magnet embedded rotary electric machine according to Embodiment 1 of the present invention. FIG. 4 is according to Embodiment 1 of the present invention. It is a flow which shows the drive control method of the external oil feeding apparatus in a permanent magnet embedded type rotary electric machine. In FIG. 1, arrows indicate the flow of cooling oil.

  1 to 3, an embedded permanent magnet rotating electrical machine 100 includes an annular stator 1, a cylindrical frame 7 that houses and holds the stator 1 inside, and bearings 12 and 13, respectively. The front frame 10 and the rear frame 11 that are disposed at both ends in the axial direction of the frame 7 and form a sealed space together with the frame 7, and the shaft 16 are supported by the bearings 12 and 13, and rotate inside the stator 1. The rotor 15, the external oil feeding mechanism 35, and the control device 40 that controls the driving of the external oil feeding mechanism 35 are provided.

  The stator 1 has an annular stator core 2 and a stator coil 4 attached to the stator core 2. The iron core block 3 includes an arc-shaped core back portion 3a and teeth 3b protruding radially inward from the circumferential center position of the inner peripheral surface of the core back portion 3a. The stator core 2 is configured in an annular shape by aligning the circumferential side surfaces of the core back portion 3a with each other and arranging 12 core blocks 3 in the circumferential direction. A concentrated winding coil 4a produced by winding a conductor wire a plurality of times is attached to the teeth 3b of each iron core block 3. The stator coil 4 is configured by the 12 concentrated winding coils 4a.

  The frame 7 is produced by fitting and integrating an aluminum cylindrical inner frame 9 inside an iron cylindrical outer frame 8. Then, the twelve core blocks 3 to which the concentrated winding coils 4a are attached are arranged in an annular shape by butting the side surfaces in the circumferential direction of the core back portion 3a, and are press-fitted and fixed in the frame 7, thereby fixing the stator 1 Is assembled.

  The rotor 15 includes an annular rotor core 17, a shaft 16 that is press-fitted and fixed in a shaft insertion hole 19 formed so as to penetrate the axial center position of the rotor core 17, and the rotor core 17. Sixteen permanent magnets 21 mounted so as to penetrate the outer peripheral side, and a first end plate 25 that is press-fitted and fixed to the shaft 16 so as to be in contact with both axial end surfaces of the rotor core 17. And a second end plate 29.

  The rotor iron core 17 is formed by stacking and integrating an annular iron core piece punched from a thin magnetic steel sheet with the through hole 18 positioned, and has a shaft insertion hole 19 penetrating the axial center position. Each of the magnet housing holes 20 has a substantially rectangular shape in which a cross section orthogonal to the axial direction of the shaft 16 is constant in the axial direction, penetrates the outer peripheral side of the rotor core 17 in the axial direction, and has an equal pitch of 8 in the circumferential direction. Paired. The pair of magnet housing holes 20 is arranged in a V shape that opens radially outward.

  Here, a portion located radially outward of the inner wall surface of the magnet housing hole 20 is referred to as an outer wall surface 20a, and a portion located radially inward is referred to as an inner wall surface 20b. In other words, the inner wall surface constituted by the radially outer long side of the cross section of the magnet housing hole 20 is the outer wall surface 20a, and the inner wall surface constituted by the radially inner long side of the section is the inner wall surface 20b. . The length direction of the long side of the cross section of the magnet housing hole 20 is defined as the width direction.

  The permanent magnet 21 has a rectangular cross section orthogonal to the axial direction of the shaft 16 and is housed in each of the magnet housing holes 20. Here, a portion located radially outward of the surface of the permanent magnet 21 is referred to as an outer surface 21a, and a portion located radially inward is referred to as an inner surface 21b. That is, the surface constituted by the long outer side in the radial direction of the cross section of the permanent magnet 21 is the outer surface 21a, and the surface constituted by the long inner side in the radial direction of the cross section is the inner surface 21b. The length direction of the long side of the cross section of the permanent magnet 21 is the width direction.

  The permanent magnet 21 housed in the magnet housing hole 20 is bonded and fixed only to the outer wall surface 20 a of the magnet housing hole 20 with an adhesive 22 only on the outer surface 21 a. As a result, the permanent magnet 21 is shifted toward the outer wall surface 20 a in the magnet housing hole 20, and a gap is formed between the inner surface 21 b of the permanent magnet 21 and the inner wall surface 20 b of the magnet housing hole 20. This gap penetrates the rotor core 17 in the axial direction and constitutes a cooling channel 23.

  The pair of permanent magnets 21 housed in the pair of magnet housing holes 20 are magnetized so as to have the same magnetic pole. The eight pairs of permanent magnets 21 are arranged so that the magnetic poles are alternately different in the circumferential direction. Here, the permanent magnet 21 is configured by arranging six magnet blocks 210 formed in a strip shape having a rectangular cross section orthogonal to the axial direction of the shaft 16 in a line in the axial direction.

  Further, the rotor grooves 24 having the groove direction as the axial direction are each formed in a groove shape having the same rectangular cross section, and are formed on the outer peripheral surface of the rotor core 17 so as to extend from one end to the other end in the axial direction of the rotor core 17. Then, eight are arranged at an equiangular pitch in the circumferential direction. The center in the circumferential direction of these rotor grooves 24 is located between adjacent magnetic poles.

  The first end plate 25 is made of a ring-shaped flat plate having an outer diameter substantially equal to the outer diameter of the rotor core 17 and having a shaft insertion hole 26 at the axial center position. The introduction flow path 27 is formed by recessing one surface of the first end plate 25 by a certain depth, leaving the outer peripheral edge thereof. The first discharge passages 28 pass through the first end plate 25 in the axial direction so as to communicate with the outer peripheral portion of the introduction flow passage 27 and the other surface side of the first end plate 25, respectively, and are equidistant in the circumferential direction. 8 are formed.

  The first end plate 25 is press-fitted and fixed to the shaft 16 from one side in the axial direction with one surface facing the rotor core 17 through the shaft 16 through the shaft insertion hole 26. One surface of the first end plate 25 is in contact with one end surface of the rotor core 17 in the axial direction, and the opening of the introduction flow path 27 is closed. A cooling channel 23 formed in the rotor core 17 is connected to the introduction channel 27. The first discharge passages 28 are located on the radially outer sides of the cooling passages 23.

  The second end plate 29 is formed as a ring-shaped flat plate having an outer diameter substantially equal to the outer diameter of the rotor core 17 and having a shaft insertion hole 30 at the axial center position. The introduction channel 31 is formed by denting one surface of the second end plate 29 by a certain depth, leaving the outer peripheral edge portion. The second discharge passages 32 pass through the second end plate 29 in the axial direction so as to communicate with the outer peripheral portion of the introduction flow channel 31 and the other surface side of the second end plate 29, respectively, and have an equal pitch in the circumferential direction. 8 are formed. Here, the second end plate 29 is formed in the same shape as the first end plate 25.

  The second end plate 29 is press-fitted and fixed to the shaft 16 from the other side in the axial direction with the one surface facing the rotor core 17 through the shaft 16 through the shaft insertion hole 30. One surface of the second end plate 29 is in contact with the other axial end surface of the rotor core 17, and the opening of the introduction channel 31 is closed. A cooling channel 23 formed in the rotor core 17 is connected to the introduction channel 31. The second discharge passages 32 are located on the radially outer sides of the cooling passages 23.

  The shaft 16 is formed in the in-axis flow path 33 and the first end plate 25 by branching in the axial direction from the in-axis flow path 33 in the radial direction. And a branch channel 34 that communicates with the introduction channel 27.

A supply pipe 36 connects the discharge port of the external oil feed mechanism 35 which is a refrigerant supply means and the inlet of the in-axis flow path 33 of the shaft 16. A return pipe 37 connects the oil pan 38 attached below the frame 7, the outlet of the in-axis passage 33 of the shaft 16, and the suction port of the external oil feed mechanism 35.
The control device 40 controls the driving of the external oil feeding mechanism 35 based on the detected temperature from a temperature detector 41 such as a thermistor disposed in the stator core 2.

  The permanent magnet embedded type rotating electrical machine 100 configured as described above is supplied with power to the stator coil 4 from an external power source, for example, and operates as an 8-pole 12-slot inner rotor type synchronous motor.

  When the external oil feed mechanism 35 is driven, the cooling oil is pumped from the supply pipe 36 to the in-shaft flow path 33 as indicated by an arrow in FIG. 27 flows in. The cooling oil flowing into the introduction flow path 27 flows radially outward through the introduction flow path 27 and flows into the cooling flow path 23. The cooling oil that has flowed into the cooling flow path 23 flows to the other side in the axial direction through the cooling flow path 23, absorbs the heat of the permanent magnet 21, and is discharged from the second discharge path 32. The cooling oil discharged from the second discharge path 32 is scattered by centrifugal force, hits the rear coil end of the stator coil 4, absorbs the heat of the stator coil 4, and is collected in the oil pan 38.

A portion of the cooling oil that has flowed radially outward through the introduction flow path 27 is discharged from the first discharge path 28. The cooling oil discharged from the first discharge path 28 is scattered by centrifugal force, hits the front side coil end of the stator coil 4, absorbs the heat of the stator coil 4, and is collected in the oil pan 38.
The cooling oil collected in the oil pan 38 is returned to the external oil feeding mechanism 35 through the return pipe 37 together with the cooling oil discharged from the outlet of the in-axis passage 33 of the shaft 16.

  According to the first embodiment, the permanent magnet 21 has the outer surface 21 a bonded and fixed to the outer wall surface 20 a of the magnet housing hole 20 and is biased toward the outer wall surface 20 a in the magnet housing hole 20. A cooling flow path 23 is formed between the inner surface 21 b of the permanent magnet 21 and the inner wall surface 20 b of the magnet housing hole 20. Therefore, since the cooling oil flowing through the cooling flow path 23 is in direct contact with the inner surface 21b of the permanent magnet 21, the permanent magnet 21 can be effectively cooled.

  An adhesive 22 for fixing the permanent magnet 21 is applied only between the outer surface 21 a of the permanent magnet 21 and the outer wall surface 20 a of the magnet housing hole 20. Therefore, the amount of adhesive 22 used is reduced, and the cost can be reduced. Further, since the cross-sectional area of the magnet housing hole 20 can be reduced by the amount of the adhesive 22 reduced, the distance between the permanent magnet 21 and the inner wall surface of the magnet housing hole 20 is shortened, and the permanent magnet 21 and the rotor core. The increase in magnetoresistance between the two is suppressed. Thereby, the fall of the magnetic flux amount of the permanent magnet 21 resulting from the increase in magnetic resistance can be suppressed.

  A rotor groove 24 is formed on the outer peripheral surface of the rotor core 17 so as to extend from one end to the other end in the axial direction. Therefore, the cooling oil leaking to the outer peripheral side from between the core pieces constituting the rotor core 17 flows through the rotor groove 24 in the axial direction. Thereby, the torque fall by cooling oil staying in the air gap between the stator core 2 and the rotor core 17 is suppressed.

  The first end plate 25 and the second end plate 29 are produced in the same shape. Therefore, the first end plate 25 can also be used as the second end plate 29, and the number of parts can be reduced.

  The first end plate 25 includes a first discharge path 28 that communicates the outer peripheral portion of the introduction flow path 27 and the other surface side of the first end plate 25. Therefore, a part of the cooling oil flowing through the introduction flow path 27 is discharged from the first discharge path 28 and exposed to the front side coil end of the stator coil 4 by centrifugal force, so that the temperature rise of the stator coil 4 is suppressed. be able to.

  The second end plate 29 includes a second discharge path 32 that communicates the outer peripheral portion of the introduction flow path 31 and the other surface side of the second end plate 29. Therefore, the cooling oil that has flowed through the cooling flow path 23 is discharged from the second discharge path 32 and is applied to the rear coil end of the stator coil 4 by centrifugal force, so that an increase in temperature of the stator coil 4 can be suppressed. .

  Here, the control of the external oil feeding mechanism 35 by the control device 40 will be described with reference to FIG. The control device 40 is set, for example, by adding a safety factor to the data in the correspondence table between the temperature detected by the temperature detector 41 and the temperature of the permanent magnet 21 and the temperature at which the permanent magnet 21 is thermally demagnetized. Stored judgment values are stored.

  First, when the motor (the permanent magnet embedded type rotating electrical machine 101) is operated, the control device 40 drives the external oil feeding mechanism 35 (step 100). Thereby, the cooling oil is supplied to the cooling flow path 23 via the in-axis flow path 33, the branch flow path 34, and the introduction flow path 27, and the permanent magnet 21 is cooled.

  Next, the control device 40 determines whether or not the motor has stopped (step 101). When determining that the motor has stopped, the control device 40 estimates the temperature of the permanent magnet 21 based on the temperature detected by the temperature detector 41 and the stored data. And it is determined whether magnet estimated temperature is below a determination value (step 102). If it is determined in step 102 that the estimated magnet temperature is equal to or lower than the determination value, it is determined that the permanent magnet 21 is sufficiently cooled, and the driving of the external oil feeding mechanism 35 is stopped (step 103). Thereby, the permanent magnet 21 is cooled by the cooling oil staying in the cooling flow path 23.

  If it is determined in step 102 that the estimated magnet temperature exceeds the determination value, it is determined that the permanent magnet 21 is not sufficiently cooled, and the driving of the external oil feeding mechanism 35 is continued (step 104). Return. Thereby, the cooled cooling oil is supplied to the cooling flow path 23 and used for cooling the permanent magnet 21.

  According to the drive control method for the external oil feed mechanism 35 according to the first embodiment, the temperature of the permanent magnet 21 is estimated based on the temperature detected by the temperature detector 41 disposed in the stator core 2, and the estimated magnet temperature Is less than or equal to a determination value, and when the estimated magnet temperature is less than or equal to the determination value, the driving of the external oil feeding mechanism 35 is stopped. Thereby, the power consumption of the external oil feed mechanism 35 can be reduced. In addition, when the estimated magnet temperature exceeds the determination value, the external oil feed mechanism 35 is continuously driven and the cooled cooling oil is supplied to the cooling flow path 23, so that an excessive temperature rise of the permanent magnet 21 occurs. And thermal demagnetization of the permanent magnet 21 can be prevented.

  In the first embodiment, the introduction flow paths 27 and 31 are formed by recessing one surface of the first end plate 25 and the second end plate 29 by a certain depth, leaving the outer peripheral edge portions. However, each of the introduction channels has a channel groove formed on one surface of the first end plate and the second end plate so as to reach the vicinity of the outer peripheral end from the shaft insertion hole, with the groove direction as the radial direction. Alternatively, eight may be arranged at an equal pitch. In this case, the first discharge plate and the second discharge passage communicate with the outer peripheral portions of the flow channel grooves and the other end sides of the first end plate and the second end plate. What is necessary is just to form through an end plate.

  In the first embodiment, the temperature detector 41 is disposed in the core back portion 3a of the stator core 2. However, the location of the temperature detector 41 is not limited to the core back portion 3a. Any place where the temperature of the permanent magnet 21 can be indirectly measured is acceptable. For example, the coil end of the stator coil 4 may be used.

Embodiment 2. FIG.
FIG. 5 is a sectional view showing a permanent magnet embedded type rotating electric machine according to Embodiment 2 of the present invention.

In FIG. 5, the in-axis flow path 33 </ b> A is formed so as to extend from one end in the axial direction at the axial center position of the shaft 16 </ b> A to a position radially below the introduction flow path 27 formed in the first end plate 25. . A branch channel 34 is formed in the shaft 16A so as to communicate the other axial end of the in-axis channel 33A with the introduction channel 27.
Other configurations are the same as those in the first embodiment.

  In the permanent magnet embedded type rotating electrical machine 101 configured as described above, the in-axis flow path 33A is formed only on the front side of the shaft 16A, so that the cost of the shaft 16A can be reduced.

Embodiment 3 FIG.
FIG. 6 is a cross-sectional view showing a permanent magnet embedded rotary electric machine according to Embodiment 3 of the present invention.

In FIG. 6, the flow path cross-sectional areas of the first discharge path 28, the cooling flow path 23, and the second discharge path 32 increase in the order of the first discharge path 28, the cooling flow path 23, and the second discharge path 32. .
Other configurations are the same as those in the first embodiment.

In the permanent magnet embedded type rotating electric machine 102 configured as described above, the flow passage cross-sectional area of the first discharge passage 28 is smaller than the flow passage cross-sectional area of the cooling flow passage 23, and thus the circulation passage through the introduction flow passage 27. The amount of cooling oil flowing out from the first discharge path 28 is limited. Thereby, the quantity of the cooling oil supplied to the cooling flow path 23 is sufficiently secured, and the cooling performance of the permanent magnet 21 is not lowered.
Since the flow path cross-sectional area of the second discharge path 32 is larger than the flow path cross-sectional area of the cooling flow path 23, the cooling oil that has flowed through the cooling flow path 23 easily flows out of the second discharge path 32. Thereby, the flow speed of the cooling oil flowing through the cooling flow path 23 is increased, and the performance of cooling the permanent magnet 21 is enhanced.

Embodiment 4 FIG.
FIG. 7 is an end view showing a rotor core in a permanent magnet embedded rotary electric machine according to Embodiment 4 of the present invention.

In FIG. 7, the magnet housing hole 20A is formed in the rotor core 17A so that both sides in the width direction of the inner wall surface 20b protrude outward in the radial direction. The protrusions on both sides in the width direction of the inner wall surface 20b of the magnet housing hole 20A constitute the support portion 43.
Other configurations are the same as those in the first embodiment.

  In the rotor 15A using the rotor core 17A configured as described above, both sides in the width direction of the inner surface 21b of the permanent magnet 21 housed in the magnet housing hole 20A are supported by the support portions 43. Therefore, since the layer of the adhesive 22 that bonds the outer surface 21a of the permanent magnet 21 and the outer wall surface 20a of the magnet housing hole 20A can be thinned, the thinner the layer of the adhesive 22, the more the magnet housing hole 20A has. A cross-sectional area can be made small and the fall of the magnetic flux amount of the permanent magnet 21 is suppressed.

Embodiment 5. FIG.
8 is an end view showing a rotor core in an embedded permanent magnet rotating electrical machine according to Embodiment 5 of the present invention, and FIG. 9 is a rotor in an embedded permanent magnet rotating electrical machine according to Embodiment 5 of the present invention. It is an end view which shows the state at the time of the motor stop of an iron core.

In FIG. 8, the magnet housing hole 20B is formed in the rotor core 17B in a V shape in which the width of the inner wall surface 20b becomes gradually narrower inward in the radial direction. Thereby, the cooling channel 23B is formed in a triangular channel cross section.
Other configurations are the same as those in the first embodiment.

  In the rotor 15B using the rotor core 17B configured as described above, the cooling channel 23B is formed in a triangular channel cross section. Therefore, even if the pressure of the cooling oil is lower than the pressure of the cooling oil supplied to the cooling channel 23 formed in the rectangular channel cross section, the cooling performance equivalent to that of the cooling channel 23 can be obtained. The power consumption of the feeding mechanism 35 can be reduced.

  Further, when the driving of the motor is stopped, as shown in FIG. 9, the contact area between the cooling oil 44 staying in the cooling flow path 23B and the permanent magnet 21 is increased. Therefore, the permanent magnet 21 can be effectively cooled by the cooling oil 44 staying in the cooling flow path 23B when the motor is stopped.

In each of the above embodiments, the case where the rotating electrical machine is applied to an electric motor has been described. However, the same effect can be obtained even when the rotating electrical machine is applied to a generator.
In each of the above embodiments, an 8-pole 12-slot rotary electric machine has been described. Needless to say, the number of poles and the number of slots are not limited to 8 poles and 12 slots.

  Further, in each of the above embodiments, the two permanent magnets constituting the magnetic pole are arranged in a V shape that is opened radially outward from the shaft. However, the arrangement of the permanent magnets is limited to this. Not. For example, the permanent magnets may be arranged at equiangular pitches in the circumferential direction so as to contact the same cylindrical surface, and each of the permanent magnets may constitute a magnetic pole.

Further, in each of the above embodiments, the permanent magnet is divided into six magnet blocks in the axial direction. However, the permanent magnet may be configured as an integrated body in which six magnet blocks are connected.
In each of the above embodiments, the permanent magnet has a rectangular cross section perpendicular to the axial direction of the shaft. However, the cross section of the permanent magnet is not limited to a rectangular shape, for example, an arc shape curved in an arc shape. Good. In this case, the magnet housing hole is formed in a cross-sectional shape that matches the cross-sectional shape of the permanent magnet.

A permanent magnet embedded rotary electric machine according to the present invention is formed by stacking and integrating an annular stator core, a stator having a stator coil wound around the stator core, and an electromagnetic steel plate, and a shaft. A rotor core that is fixed to the stator core and rotatably disposed inside the stator core, and a plurality of magnets that are formed so as to penetrate the outer peripheral side of the rotor core in the axial direction and are arranged in the circumferential direction. And a rotor having a permanent magnet housed in each of the magnet housing holes. And the adhesive is disposed only between the outer wall surface located radially outward of the inner wall surface of the magnet housing hole and the outer surface located radially outward of the surface of the permanent magnet, A permanent magnet is offset to the outer wall surface of the magnet housing hole, and a cooling flow path through which the refrigerant flows is an inner surface located radially inward of the surface of the permanent magnet and a diameter of the inner wall surface of the magnet housing hole. An inner wall surface located inward in the direction, and the magnet housing hole protrudes from both sides in the width direction of the inner wall surface of the magnet housing hole, and both width direction side portions of the inner surface of the permanent magnet. that it has a support portion for supporting the.

Next, the control device 40 determines whether or not the motor has stopped (step 101). Controller 40 determines that the motor has stopped, on the basis of the data stored with the temperature detected by the temperature detector 41 estimates the temperature of the permanent magnet 21. And it is determined whether magnet estimated temperature is below a determination value (step 102). If it is determined in step 102 that the estimated magnet temperature is equal to or lower than the determination value, it is determined that the permanent magnet 21 is sufficiently cooled, and the driving of the external oil feeding mechanism 35 is stopped (step 103). Thereby, the permanent magnet 21 is cooled by the cooling oil staying in the cooling flow path 23.

Claims (8)

An annular stator core, and a stator having a stator coil wound around the stator core;
Constructed by laminating and integrating electromagnetic steel plates, fixed to a shaft and arranged to be rotatable inside the stator core, each formed so as to penetrate the outer peripheral side of the rotor core in the axial direction In a permanent magnet embedded type rotating electrical machine comprising a plurality of magnet housing holes arranged in the circumferential direction, and a rotor having a permanent magnet housed in each of the magnet housing holes,
The permanent magnet is disposed only between the outer wall surface located radially outward of the inner wall surface of the magnet housing hole and the outer surface located radially outward of the surface of the permanent magnet. Is offset to the outer wall surface of the magnet housing hole,
The cooling flow path through which the refrigerant flows is configured by an inner surface positioned radially inward of the surface of the permanent magnet and an inner wall surface positioned radially inward of the inner wall surface of the magnet housing hole. Permanent magnet embedded rotary electric machine. A first end plate fixed to the shaft and disposed so that one surface is in contact with one axial end surface of the rotor core;
An in-axis flow path is formed to extend in the axial direction at the axial center position of the shaft,
A branch channel is formed in the shaft so as to branch radially from the in-axis channel and reach the outer peripheral surface of the shaft,
An introduction channel is formed on the one surface of the first end plate so as to communicate the branch channel and the cooling channel;
2. The permanent plate according to claim 1, wherein the first discharge path is formed in the first end plate so as to communicate the outer peripheral portion of the introduction flow path and the other surface side of the first end plate. Embedded magnet type rotating electrical machine.   The embedded permanent magnet type rotating electric machine according to claim 2, wherein the in-axis flow path is formed only in an axial region from one axial end of the shaft to a fixing position of the first end plate. . A second end plate fixed to the shaft and disposed so that one surface is in contact with the other axial end surface of the rotor core;
A second discharge path is formed in the second end plate so as to communicate with the cooling channel and the other surface side of the second end plate;
The flow passage cross-sectional area of the first discharge passage is smaller than the flow passage cross-sectional area of the cooling flow passage, and the flow passage cross-sectional area of the second discharge passage is larger than the flow passage cross-sectional area of the cooling flow passage. The permanent magnet embedded type rotating electric machine according to claim 2 or 3, wherein   The magnet housing hole includes a support portion that protrudes from both sides in the width direction of the inner wall surface of the magnet housing hole and supports both sides in the width direction of the inner surface of the permanent magnet. The embedded permanent magnet rotating electric machine according to any one of claims 1 to 4.   The inner wall surface of the magnet housing hole is formed in a shape that narrows the width inward in the radial direction, and the cross-sectional shape orthogonal to the axial direction of the shaft of the cooling channel is configured in a triangle. The permanent magnet embedded rotary electric machine according to any one of claims 1 to 4, wherein:   A plurality of rotor grooves are formed on the outer peripheral surface of the rotor core from the one end to the other end in the axial direction with the groove direction as the axial direction, and a plurality of rotor grooves are arranged in the circumferential direction. The embedded permanent magnet rotating electrical machine according to any one of claims 1 to 6. Refrigerant supply means for supplying the refrigerant to the cooling channel;
A temperature detector for indirectly detecting the temperature of the permanent magnet;
A control device for controlling the driving of the refrigerant supply means,
The control device estimates the temperature of the permanent magnet based on the temperature detected by the temperature detector, and when the estimated temperature of the permanent magnet is equal to or lower than a determination value, stops the driving of the refrigerant supply means, The permanent magnet according to any one of claims 1 to 7, wherein when the estimated temperature exceeds the determination value, the refrigerant supply means is continuously driven. Embedded rotary electric machine.

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